Shearing machine

ABSTRACT

Hydraulic sheet-metal shearing machine comprising a movable apron pivotally mounted about an eccentric axis of rotation of adjustable angular position permitting of modifying at will the initial clearance between the blades. The support of the sheet abutment device is hingedly mounted to the movable apron about an axis shifted in relation to the pivotal axis thereof, and which has likewise an eccentric position. The shafts materializing these two axes are operatively interconnected through means capable of correcting the position of said abutment device when the clearance between the blades is modified by pivoting the eccentric hinge shaft of said movable apron.

United States Patent [191 Cailloux 1 SHEARING MACHINE I v [75] Inventor: Paul Cailloux, Le Perreux, France [73] Assignee: Promecam Sisson-Lehmann,

Saint-Denis, France [22] Filed: Nov. 9, 1971 [21] Appl. No.: 196,959

[30] Foreign Application Priority Data Nov. 13, l970 France 7040579 [52] US. Cl 83/391, 83/527, 83/612, 1 83/700 [5 l] Int. Cl B26d 5/02, 826d 7/16 [58] Field of Search 83/391, 395, 527, 83/530, 699, 700, 640, 612

[56] References Cited UNITED STATES PATENTS 3,260,145 7/1966 Giordano 83/391 FOREIGN PATENTS OR APPLICATIONS 805,806 l2/l958 Great Britain 83/391 1111 3,742,801 [451 July 3, 1973 603.808 4/ 1960 ltaly 133/39] Primary Examiner-Frank T. Yost Attorney-Michael S. Striker ABSTRACT Hydraulic sheet-metal shearing machine comprising a movable apron pivotally mounted about an eccentric axis of rotation of adjustable angular position permitting of modifying at will the initial clearance between the blades. The support of the sheet abutment device is hingedly mounted to the movable apron about an axis shifted in relation to the pivotal axis thereof, and

which has likewise an eccentric position. The shafts materializing these two axes are operatively interconnected through means capable of correcting the position of said abutment device when the clearance between the blades is modified' by pivoting the eccentric hinge shaft of said movable apron.

3 Claims, 5 Drawing Figures SHEARING MACHINE The present invention relates to hydraulic shearing machines for cutting sheet metal, of the type comprising an apron to which the movable blade is secured.

This apron may be arranged at the upper portion of the machine for cutting the metal sheets by means of a downward stroke or movement. However, the reverse apron disposal may also be contemplated, and in this case the metal is cut by producing an upward movement or stroke. In either case the hinge axis of the movable apron is located behind the uprights of the frame structure of the machine.

This invention is concerned more particularly with shearing machines of this type, wherein the movable apronis hingedly mounted about an eccentric rotary shaft of which the angular position is adjustable to permit a modification in the initial clearance between the blades. In fact, this invention aims at providing a number of improvements in shearing machines of this general type. I p

The first improvement contemplated according to this invention consists inobtaining through very simple means the automatic backward movement of the sheet abutment device during the cutting or shearing operation, by mounting this device on a hinge shaft carried by the movable apron but separate from the hinge shaft proper of this apron.

However, this arrangement is likely to produce an untimely and undesired movement of the abutment device when the initial clearance of the blades is modified by rotating the eccentric pivot shaft of the movable apron. Therefore, according to a second improvement contemplated by this invention the abutment device is either kept in a constant position in this case, or moved forwards or backwards, in a predetermined ratio, as a function of the adjustment of the blade clearance.

To this end, the pivot member of the abutment device is also mounted about an eccentric shaft or pin and on the other hand connecting means, capable of correcting the position of said abutment device when the initial clearance between the blades is modified by rotating said eccentric shaft or pin, are provided between said pivot member and said eccentric shaft or pin.

However, other features and advantages of the improved hydraulic shearing machine according to this invention will appear as the following description proceeds with reference to a typical form of embodiment thereof. This description is given by way of example with reference to the attached drawing, in which:

FIG. 1 is a cross-sectional view showing the shearing machine according to this invention;

FIG. 2 is a fragmentary view showing on a different scale the hinged mounting of the movable apron and of the abutment device, this view corresponding to a section taken along the line II-II of FIG. 1;

FIG. 3 is a corresponding diagrammatic elevational view; and FIGS. 4 and 5 are views similar to FIGS. 2 and 3 and illustrate a modified embodiment.

The hydraulic shearing machine illustrated in the drawing comprises a pair of side plates 1 braced by a box-sectioned member 2 and stiffened by an inclined plate 3 welded to said member 2 and stiffened by an inclined plate 3 welded to said member 2 and to the upper fixed apron 4 in order to form the frame structure of this machine. The apron 4 carries a fixed blade 5 secured to the lower edge of its rear face, as shown in FIG. 1. The movable blade 6 is secured to the upper edge of a support 7 constituting an element of the movable apron structure 8 of the machine. The movable blade 6 is disposed behind the sheet clamping members 9 overlying the table orworkingbed 10 of the machine.

Underlying this table 10 is a motor and pump unit 1 1 adapted to supply hydraulic fluid under pressure to the hydraulic circuit (not shown) controlling the piston and cylinder units 12 actuating the movable apron 8.

The movable apron 8 comprises a pair of lateral plates 13 assembled by the blade support 7 and also by a box-sectioned member 14 having an inclined upper face or top constituting a chute for removing the cut metal strips or blanks.

This movable apron 8 is pivotally mounted on either side to an eccentric ring 15 adapted to rotate in turn about a stub shaft 16 carried by the corresponding lateral plate 1 of the frame structure of the machine. A rolling-contact bearing 17 is interposed between the corresponding portion of the movable apron 18 and each ring 15.

Each ring 15 carries a control lever 18 so that the angular position of the two rings may be modified at will to change the initial clearance existing between the movable blade 6 and the fixed blade 5.

The control lever 18 is rigid with a lock pin 19 engageable in either .of a series of retaining holes formed in a fixed plate 20 rigidwith the corresponding side plate 1 of the frame structure. Thus, the movable apron can be locked in the position corresponding to the desired clearance between the twoblades of the machine.

According to an essential feature characterizing this invention the-sheet abutment device 21 is mounted on a support consisting of a pair of rails 22 having their rear ends pivoted to the movable apron at a point 23 overlying the general hinge shaft 16 of this apron.

Under these conditions, these two rails are moved backwards when the movement of the movable apron is started for cutting or shearing the metal stock. Thus, the abutment members are caused to recede automatically during the shearing operation.

However, means are provided for correcting the position of the abutment members when'the initial clearance of the blades is modified by rotating the pivot rings 15 of the movable apron. In fact, this operation normally tends to produce a movement of the abutment members since the support thereof is pivoted to the movable apron.

The correction device contemplated is so designed that in case of such modification in the play between the blades it will either keep the abutment device 21 in a constant position or move same forwards or backwards as a function of the modified adjustment of the blade clearance, in a predetermined ratio.-

To obtain this result the rails 22 carrying the abutment members are each pivoted about an eccentric socket 24 mounted for free rotation on a pin 23 carried by the movable apron 8. On the other hand, connecting means are provided between this socket 24 and the eccentric ring 15 on which the apron is pivoted, in order to correct the position of the support of said abutment members.

These connecting means may comprise a toothed pinion 25 rigidly connected to the ring 15 through an end cap 26 and in constant meshing engagement with a toothed segment 27 rigid in turn with the eccentric socket 24.

Thus, when the ring is rotated by means of its control lever 18 and it is desired to modify the initial clearance between the blades, this movement is attended by a rotation in the opposite direction of eccentric socket 24 and therefore by a movement of the support of said abutment members in the proper direction for correcting its displacement caused by the movement of the movable apron.

But it is also possible to obtain a rotation of the eccentric socket 24 in the same direction as the ring 15 and the lever 18. To this end it is sufficient to provide an intermediate toothed pinion 28 between the pinion 25 and the segment 27 shown in FIGS. 4 and 5.

The correction thus obtained may have a twofold purpose: either maintaining the abutment members in a constant position, or producing their movement in a predetermined ratio.

The shearing machine according to this invention is adapted to be used for shearing sheets of any metal. However, it will readily occur to those conversant with the art that this shearing machine should not be construed as being limited by the specific form of embodiment illustrated and described herein, since various modifications and variations may be brought thereto without departing from the basic principles of this invention. Thus, the movable apron of the shearing machine illustrated may if desired be mounted in the upper portion instead of the lower portion of the machine.

What l'claim is:

1. Hydraulic sheet-metal shearing machine comprising a structure, a movable apron pivotally mounted on said structure about an eccentric axis, two shearing blades which are solid respectively with said structure and with said apron, an abutment device for the sheet to be sheared, a support for said device, said support being hingedly mounted to the movable apron about an axis shifted in relation to the pivotal axis thereof, and which has an eccentric position, connecting means between said axes, said means being adapted to correct the position of said abutment device when the clearance between the blades is modified by pivoting the eccentric hinge axis of said movable apron.

2. Hydraulic shearing machine according to claim 1, in which said connecting means provided between said eccentric axes of the movable apron and of the support of said abutment device consist of a toothed pinion rigid with one of these axes and in constant meshing engagement with a toothed segment rigid with the other axis. v

3. Hydraulic shearing machine according to claim 1, in which said connecting means provided between said eccentric axes of the movable apron and of the support of said abutment device consist of a toothed pinion rigid with one of these axes and in constant meshing engagement with a free toothed pinion in meshing engagement with a toothed segment rigid with the others axis. 

1. Hydraulic sheet-metal shearing machine comprising a structure, a movable apron pivotally mounted on said structure about an eccentric axis, two shearing blades which are solid respectively with said structure and with said apron, an abutment device for the sheet to be sheared, a support for said device, said support being hingedly mounted to the movable apron about an axis shifted in relation to the pivotal axis thereof, and which has an eccentric position, connecting means between said axes, said means being adapted to correct the position of said abutment device when the clearance between the blades is modified by pivoting the eccentric hinge axis of said movable apron.
 2. Hydraulic shearing machine according to claim 1, in which said connecting means provided between said eccentric axes of the movable apron and of the support of said abutment device consist of a toothed pinion rigid with one of these axes and in constant meshing engagement with a toothed segment rigid with the other axis.
 3. Hydraulic shearing machine according to claim 1, in which said connecting means provided between said eccentric axes of the movable apron and of the support of said abutment device consist of a toothed pinion rigid with one of these axes and in constant meshing engagement with a free toothed pinion in meshing engagement with a toothed segment rigid with the others axis. 